Crash before saving in 2.10.6
I closed the only image I had open. That image was made by pasting a screenshot into the window and cropping it, then pasting in part of another screenshot (I was comparing the behaviour of dialog boxes). Thus the image had never been loaded, saved, or exported. When I closed the window, GIMP prompted me to save the image. I opted to save the image, whereupon GIMP crashed.
The gimp-crash.txtgimp-debug-tool crash log is attached.